This discussion may contain spoilers!
When you had the choice of cutting off Sarita's arm (if you cut it off) maybe it was a mistake?
The axe had been in zombie's stomach so you should probably wash it before cutting off anyone's hand.
Now Sarita still has the infection (maybe) and she will turn. If you chose to kill the zombie you'll find some clean weapon to cut it off.
But then Sarita could not stand the pain so she's not going to let that happen.
So this leaves Sarita dead no matter what you do.
Let the dislikes come.